Initial test results suggest two more people in Liberia have been infected with Ebola, both of whom had contact with a boy who recently died from the disease. And responders made little progress in their battle against the virus last week in Guinea and Sierra Leone.

If further tests confirm the infections, Liberia would have three new Ebola cases, signaling a growing threat of virus spread in an area not far from Monrovia. Meanwhile, the other two countries reported 20 new lab-confirmed cases last week, the same as the previous week, the World Health Organization (WHO) said today in its weekly epidemiologic update on the outbreak.

The overall total in the three outbreak countries is at 27,514 confirmed, probable, and suspected Ebola infections, including 11,220 deaths, the WHO said.

More test positive in Liberia

Media reports today said at least two more cases have been detected in Liberia, which went 3 months with no new cases, until officials on Jun 29 announced that the virus had been detected in a 17-year-old boy who died at his home in a rural Margibi County village reported as Nidowein (or Nidowin), about an hour's drive (about 36 miles) southeast of Monrovia and a short distance west of the country's Roberts International Airport.

County health department spokesman Cestus Tarpeh said the two people had physical contact with the boy before he died. He told Agence France-Presse (AFP) that officials are still waiting for further blood test results.

Liberia's information ministry today tweeted that tests have confirmed Ebola infections in two people from the boy's home.

So far investigators haven't determined how the boy was exposed to the virus. The WHO said in its update today that he had no recent history of travel, contact with visitors from affected areas, or funeral attendance.

The boy had his first symptoms on Jun 21 and was treated for a presumed malaria infection, according to the WHO. He died on Jun 28, and oral swabs taken twice before he was safely buried tested positive for Ebola.

Moses Massaquoi, MD, MPH, a case manager for the response team, said the boy's body was exhumed yesterday so that a blood sample could be obtained, the New York Times reported yesterday. He said the sample, which was positive, might help scientists determine if the source is an isolated outbreak or a new strain of the virus.

He said late yesterday that one of the boy's contacts tested positive and that results for two others were inconclusive, according to the Times report. He said three people will be sent to a treatment unit in Monrovia

So far 102 contacts have been identified, with the number expected to increase, the WHO said. Liberian health officials have beefed up surveillance in the area and have quarantined two households, according to earlier reports.

Progress still stalled in Guinea, Sierra Leone

In other outbreak developments, Guinea and Sierra Leone last week reported 20 more lab-confirmed cases, the same as the week before, the WHO said, noting that weekly case incidence has varied from 20 to 27 for the past 5 weeks.

Guinea's 12 cases were from the same three areas that reported cases the previous week: Boke and Forecariah districts and Conakry. Sierra Leone's 8 cases were also from the same areas reported the week before: Kambia, Port Loko, and Freetown, the WHO said.

Each country reported identical case numbers last week.

Though the affected areas of Guinea are same, the Ebola transmission pattern is evolving, the WHO reported. Nine of 10 cases from the country's Boke district involved known contacts, 1 of whom is a health worker. Another case-patient from Boke is also a health worker, with an illness that has generated a number of high-risk contacts. Forecariah district's single case arose from a registered contact of an earlier case.

The one case reported from Conakry is in Dixinn, the city's third community to report an illness in the past 4 weeks. The new case in the capital arose from an unknown transmission source.

Meanwhile, Sierra Leone's new cases came from several chiefdoms in Kambia and Port Loko districts, with 4 of the country's 8 cases coming from Freetown's Magazine Wharf neighborhood. The latest cases in the Freetown cluster all have links to earlier cases, but health officials still haven't identified the index case.

Overall, 10 of Guinea's 12 cases and 4 of Sierra Leone's 8 cases came from known contacts, and 5 cases were detected only after people had died in the community. Cases in unknown transmission chains and postmortem infection detections are two markers that show sick patients are not being isolated and treated, posing ongoing threats to the community.

The two new healthcare worker infections in Guinea boost the overall number to 874 such illnesses, 509 of them fatal.